Abstract:To meet the Chinese GB regulations (Equivalent to Euro V) and to adsorb the excess hydrocarbons emitted during a period of engine cold-start, in addition, Hydrocarbon (HC) adsorption behavior on Pd-based catalyst appeared during a cold-start period of actual driving cycle in the vehicles of, Dragon and Cherry, therefore, we leaded in HCA (Hydrocarbon Absorber) material. Catalytic performance of prepared HCA catalyst and HC adsorption process were tested, and then their applications were studied in the whole vehicle. In this work, Pd /Ce-HZSM-5 was used as the main recipes of HCA materials as well as a combination of zeolite and precious metals. For Dragon and Cherry models, their emission results show Pd/Ce-HZSM-5 catalyst is superior to conventional catalyst for HC trap. Since Pd-based catalyst showed relatively good light-off performance, the combination of HC adsorption and early light-off activity has led to an improvement of overall HC emission reduction to Pd/Ce-HZSM-5. Use of zeolite combined with Pd-based catalyst caused maximize HC adsorption between 20-30 s during the cold-start period at fresh. HCA material has great research potential to meet high standards of HC emissions quality at low temperature.